Apparatus for obtaining in a zig-zag sewing machine an automatic displacement of thefabric apt to be amplitude adjusted



t 00 w 2 h 7 00 w 2 e e W h W S E 6 S G A 4 Feb. 21, 1961 o o APPARATUSFOR OBTAINING IN A ZIG MACHINE AN AUTOMATIC DISPLACEMENT OF THEFABRICAPT TO BE AMPLITUDE ADJUSTED Flled Aug 2, 1955 Inventor An nioMot-a w y W 2% 1 Mme Feb. 21, 1961 A. MORO APPARATUS FOR OBTAINING IN AZIG-ZAG SEWING MACHINE AN AUTOMATIC DISPLACEMENT OF THE FABRIC APT TO BEAMPLITUDE ADJUSTED 6 Sheets-Sheet 2 Filed Aug. 2, 1955 mm 9? \m mm mmInventor A-nZ o-n 4o Moro y v wneys Feb. 21, 1961 o o APPARATUS FOROBTAINING IN A ZIGZAG SEWING MACHINE AN AUTOMATIC DISPLACEMENT OF THEFABRIC APT TO BE AMPLITUDE ADJUSTED Flled Aug 2, 1955 6 Sheets-Sheet 3Inventor Anion [o ore y 8 @5 4 W? I ttorneys Feb. 21, 1961 MQRQ2,972,319

APPARATUS FOR OBTAINING IN A ZIG-ZAG SEWING MACHINE AN AUTOMATICDISPLACEMENT OF THE FABRIC APT TO BE AMPLITUDE ADJUSTED Filed Aug. 2,1955 6 Sheets-Sheet 4 I n ventor AflfOTILb Mal-0 7 y 7 7, H WAttorneys IFeb. 21, 1961 o o APPARATUS FOR OBTAINING IN A ZIG-ZAG SEWING MACHINE ANAUTOMATIC DISPLACEMENT OF THE FABRIC APT TO BE AMPLITUDE ADJUSTED FlledAug 2, 1955 6 Sheets-Sheet 5 Inventor A12 L 07? L o Mora y Z W 211M247 tAttorneys Feb. 21, 1961 A. MORO 2,972,319

APPARATUS FOR OBTAINING IN A ZIG-ZAG SEWING MACHINE AN AUTOMATICDISPLACEMENT OF THE FABRIC APT TO BE AMPLITUDE ADJUSTED Filed Aug. 2,1955 6 Sheets-Sheet 6 Inventor A'n Z 071 (O M -0 Antonio Moro, Milan,Italy, assignor to F.lli Borletti S.p.A., Milan, Italy Filed Aug. 2,1955, Ser. No. 525,935 Claims priority, application Italy Aug. 6, 1954 6Claims. (Cl. 112-158) The present invention relates to an apparatus, by

means of which it is possible, in a zig-zag sewing machine, to cause thedisplacement of the fabric to automatically respond to a previouslydetermined cycle, said apparatus allowing at the same time for theadjustment of the amplitude of this displacement.

The apparatus according to the present invention is characterized by acam being able to be rechangeably mounted on a rear extension of theshaft of the cam for producing the cross displacement of the needle barfor 'the zig-zag sewing operation, said cam positioned on the rearextension of said shaft having the task of actuating the means fordriving the fabric feeder through alever, the pivot of which isdisplaceable, by a hand driven mechanism, preferably according to an arcof circle in such a manner as to be able to adjust through itsdisplacement the oscillation that the lever driven by the cam transmitsto the means for driving the fabric feeder.

The amplitude of the fabric feeder movement, ensured by the camcontrolling its cycle, can thus be adjusted at will.

As to the means for driving the fabric feeder, it can consist in themechanism of known kind generally employed in the sewing machines forcausing said feeder to work.

However, it has been ascertained that in certain cases this kind ofmechanism can give place to drawbacks capable of troubling the regularworking of the machine.

For instance a remarkable strength is necessary for keeping saidmechanism in a determined position and, as it is held in contact withthe lever actuated by the automatic driving cam by means of a spring,the latter must be excessively strong, which jeopardizes the facility ofmovement of the machine.

The present invention provides, as complemental means of the apparatusforming the subject matter thereof, a device for controlling andadjusting the travel of the fabric feeder, which device, as iteliminates all the drawbacks of the mentioned mechanisms, assures to thesewing machine a perfect working.

This device is characterized by the fact that an oscillating fork,driven by an eccentric fixed on the upper main shaft of the sewingmachine, carries parallel to its oscillation plane, a guiding pin, uponwhich is slidably mounted a runner pivoted on the link effecting theadvancement of the fabric feeder, a cross lever or, more precisely, alever with two branching arms extending therefrom in oppositedirections, serving for varying the position of said runner on itsguiding pin, said cross lever being mounted on the same oscillation pinof the fork and being arranged in such a manner as to be able to beactuated either through one of its branching arms, automatically,according to a previously determined cycle, by the lever driven by thecam turning in synchronism with the main shaft of the machine, or,through the-other branching arm, by a hand lever. A spring is providedto keep the cross lever adherent either to the hand driven ice lever orthe lever driven by the cam; and as the runner, Whatever position it maybe made to take up, that is also when it is brought on the guiding pinin the position of maximum distance from the oscillation center of thefork, under the maximum raising strength of the fabric, does not tend togo by itself to the zero position. Said spring can be very light, whichis advantageous for the strengths of the cam, the movement facility ofthe machine and the regularity of the stitch.

Of course, the variation of the travel of the link driven by the runneror slider and consequently the variation of the stitch length depend onthe position of said runner or slider.

In the described device the two drives of the adjustment by cam and byhand, can work either simultaneously or separately, in the latter casebeing excluded one or the other drive.

An embodiment of the apparatus according to the present invention isshown by way of example, as applied to a zig-zag sewing machine withvariable sewing cycle of the kind as in my copending patent applicationSerial No. 525,177, in the annexed drawings, in which:

Fig. 1 is a longitudinal section of the zig-zag sewing machine;

Fig. 2 is across section of the same according to the line A-A of Fig.1.

Fig. 3 is a cross section of the same according to the broken line B-Bof Fig. 1.

Fig. 4 is a cross section according to the line CC of Fig. 1.

Fig. 5 is a cross half section showing a modification of Fig. 4concerning the mounting of the cam for displacing the fabric. 7

Fig. 6 is a cross half section showing another modification of Fig. 4concerning the mounting of the cam for displacing the fabric.

Fig. 7 shows a partial longitudinal section of the machine according tothe line D-D of Fig. 4.

Fig. 8 shows in longitudinal section the device for controlling thefabric feeder, said device being applied onto the machine.

Figs. 9 and 10 are two cross sections according to the line EE of Fig.8, said figures showing said device in two different working conditions.

Fig. 11 is a partial rear view according to the arrow F of Fig. 10. 1

Fig. 12 shows the particular of the runner or slider.

The main shaft 1 (Fig. 1), mounted in the upper portion of the frame 2of the machine, transmits a reciprocating up and down movement to theneedle bar '5 by means of the crank pin 3 and the spring connecting rod4. The cross movement for the zig-zag sewing operation is transmitted tothe needle bar by the same shaft 1 throughthe worm 6 and worm wheel gear7, the shaft 8, a cam 25 mounted on the shaft 8, the two arms lever 9,10 actuated by said cam, the oscillating support 11 actuated by the arm10 of said lever, the shaft 12 sliding in said support and the rod 13pivoted, at one of its ends, on the shaft 12 and connected, at the otherend, to the support 14 of the needle bar, fixed in 15 to the frame 2 bymeans of the small elastic plate 16. The main shaft 1 (Figs. 1 and 2)also actuates, by means of its crank 17, the link 18, the lever 19, theshaft 20 and the bevel toothed wheels 21 and 22, the hook 23, whichcooperates with the needle 24 for producing the sewing operation. Thecam mounted and secured on the shaft 8 for forming in known manner thezig-zag sewing is that indicated in the drawings (Figs. 1 and 3) with25. On the hub of this cam, however, a second cam 26 (Fig. 3) can bemounted in such a manner as to be able to be changed for varying thezigzag cycle and for passing from one sewing cycle to another one whilethe lever 9-10 can be transferred from one of said cams to the otherone, by causing it to slide by an actuation member (not shown) on bothits rotation pin 27 and the pin 28, which is carried by the support 11and on which said lever is mounted by the fork end of its arm 10. Theoscillation pin 29 of the support 11 is connected, by means of thesupport 30 and the arm 31 to the piece 32 pivoted on the shaft 33 andcarrying the small plate 34 fixed thereupon, said plate at its upper endbeing rigidly connected to the maneuvering button 35. On the pivotingpin 36 of the rod 13, which is located on the shaft 12 is pivoted thearm 37, which at its lower end is pivoted by means of the pin 38 on thesleeve 39, the latter having a projection 40 upon which is mounted thestem 41 of an actuating button 42. Thus, by acting on the buttom 35, theangular position of the support 11 and therefore the cross origin of thezig-zag stitch is varied. By acting on the button 42, one varies, bydisplacement of the shaft 12, the position of the pin 36 and the rod 13with respect to the support 11 and, therefore, the oscillation amplitudeof said rod, with consequent variation of the amplitude of the sewingzig-zag. The maneuvering movement of the button 42 in the relatingwindow can be limited by stops 43 applied in said window and blockedeach by a button 44 having threaded stem. These stops, however, can besurmounted by the button 42, when it is pushed towards the interioragainst the action of the spring 45, so as to bring in correspondencewith said stops the portion 41' of the stem 41. Thus, button 42 is freeto move to a new position, whereupon button 42 is released, and spring45 moves the stem 41 back into engagement with the stops 43.

According to the present invention, on the rear extension 8' of theshaft 8 (Fig. 4) is mounted a cam 46 locked by means of a nut 47 on aflange 48, which can be either fixed on the shaft 8 (Fig. 4) or mountedin a bearing 49 fixed to the frame 2, said flange being connected to ahub 50 fixed on 8', in such a manner as to be able to be caused to turnby means of either a joint 48 (Fig. or a gear 50' (Fig. 6). In the lastcase the advantage is obtained that the speed ratio between the shaft 8'and the cam 46 can be varied by varying the ratio of the teeth on hub 50and flange 48.

The periphery of the cam 46 (Fig. 7) is kept in contact with the smallpin 51 carried by the arm 52 of the two arm lever 52, 53, the other armof which carries a small pin 54 capable of being brought into contactwith the projection 55 of the lever 56 driving the mechanism of knownkind which transmits the movement to the fabric feeder.

The lever 52, 53 is pivoted at 57 on a support 58 pivoted on a shaft 59and rigidly connected to an arm 60 bearing on an eccentric 61.

With the described arrangement the rotation of the cam 46 causes areciprocating movement of the lever 52, 53 and, therefore, of theprojection 55 which by means of a spring 62 (Fig. 2) is kept in contactwith the small .pin 54. Correspondent displacements are thus repeated bythe projection 55 and thus by the lever 56, so that to the fabric can beimparted forward and backward displacements, said displacementsresponding to the cycle determined by the shape of the cam 46. Byadjusting the angular position of the eccentric 61 by means of thebutton 63 and thus displacing by the arm 60 the angular position of thepin 57 on an are 64 (Fig. 7), the displacemerits of both the pin 54 andthe projection 55 can be varied both in absolute value and with respectto the movement of the needle bar, so as to obtain by the same camdisplacements of the fabric of different amplitude according to theposition given to 61.

Under the angular positions that the eccentric 61 can be given, there isone at least for which the pin 54 is completely removed from theprojection 55, so that it has no more influence on the advancement ofthe fabric. Under these conditions, the lever 65 can be caused to work,by maneuvering it by hand by means of the button 66, said lever throughthe pin 67 coming then into contact with the lever 56 is moved free ofthe pin 54 and biased by the spring 62. The displacement of the fabrictakes place by hand, in the manner known for the sewing machines.

The cam 46 (Fig. 4) can be easily substituted with any other cam havinga different profile simply by unscrewing the nut 47. Between the cam 46and the flange 48 can be arranged a spring 68 to facilitate the removalof cam 46. It is not necessary to remove the cam 46, when it is alreadymounted, for passing from the drive for displacing the fabric by cam tothe drive for displacing it by hand.

In order to be able to effect the mounting and the re moval of the cam46, in the rear wall of the frame 2, opposite thereto, is provided awindow closed by a plate 69, said window corresponding to the one closedby the plate 70, which is located in the opposite wall for both themounting and the removal of the removable cam 26 for the zigzag sewingoperation.

The lifting of the fabric feeder 71 (Figs. 1 and 2) is effected by a cam72 mounted on the oscillating shaft 20, which drives the hook 23. On thecam 72 bears a lever 73, pivoted at 74, on the other end of which thepin 76 is mounted. The end 77 of the movable support 78 of the fabricfeeder 71 bears on this pin 76, a spring 79 keeping the support, bymeans of the lever 73, biased towards the cam 72. The pin 76 is axiallyslidable in such a manner as to be able to be disengaged from the end 77of the support 78, thus removing the fabric feeder from the drive of thecam 72. The fabric feeder then remains in a downward position and themachine can effect embroidery work for which the fabric is displaced byhand.

The pin 74 is secured in the bush 30, which is adapted to be displacedand fixed in a position chosen in any manner on the pin 81 by means ofscrew By this system the projecting portion of the fabric feeder can beeasily adjusted.

In the foregoing description it was assumed (Figs. 1 to 7), that themeans for driving the fabric feeder might consist of the mechanism asusually employed to this end in the sewing machines of known kind.

However, as it was already stated, a better drive of the fabric feederensuring a perfect working of the machines, is obtained by means of thedevice forming the subject matter of the invention, which is illustratedas applied on a zig-zag sewing machine in Figs. 8 to 12.

In this device, the fork 82 is caused to oscillate on the pin 83 by thecam 84 mounted on the upper shaft 1 of the machine. A guiding pin 85 isfixed to the projections 86, 87 rigidly connected to the fork 82.

The guiding pin 35 accomplishes about the pin 83 the same oscillationsof the fork 82, that is it displaces itself, at each revolution of thecam 84 from the position X-X to the position Y-Y, returning to theposition XX at the end of each revolution. If the center 92 of therunner or slider 88, which is displaced on the pin 85 from one end 89 tothe other end 99 of said pin and vice versa, coincides with the axis ofthe pin 83, said slider remains immovable and the link 91, pivoted at92, does not receive any axial displacement. If the center 92 of therunner or slider 88 is displaced towards the end 86, it receivesdisplacements from X to Y according to the arrow 93 and returns. If thecenter 92 of the runner or slider 88 is displaced towards the end 87, itreceives opposed displacements, that is according to the arrow M andreturns.

The link 91 consequently receives corresponding displacements. As thelink 91 is connected by means of the parts 95, 96 (Fig. 2) to thesupport 73 of the fabric feeder 7i, consequently also said feeder 71, insynchronism with the feeder lifting means 75, moves from a forwardposition to a backward position or from a backward position to a forwardposition, in response to the position of the runner or slider 88 on thepin 85. The more the runner or slider 88 is displaced from the pin 83,the greater will be its displacement in the sense of the arrows 93, 94and the greater will be the travel of the link 91 and consequently ofthe feeder 71.

It is sufiicient to displace the runner or slider 88 from the pin 83 ofa given distance and towards the determined side with respect to the pin83 for obtaining the desired displacement length and direction of thefabric for each stitch.

As the maximum necessary inclination of the guiding pin 85 upwards ordownwards with respect to its middle position -0 is small, that is ofabout 6, it is easy to understand that it is not necessary to have agreat strength for causing the runner or slider 88 to slide on the pin85, and that moreover the oscillation of the fork 82 does not tend tomake the runner or slider 88 return to the central position (axis 83),so that a small force is sulficient for keeping said runner in anydetermined position.

The displacement of the runner or slider 88 is caused by the cross lever97 pivoted on the pin 83. The projection 97 carries a pin with a slipper98 which is retained in the fork 99. The fork 99 is secured to the link91 on the upper portion of which is pivoted the runner or slider 88which is held on the opposite side by the small plate 99. 1

The drive can be imparted to the lever 97 by two separate parts, ofwhich, one 100 is connected to a lever 101 adapted to be actuated byhand from the outside of the frame and the other 102 is actuated by thelever 52 automatically driven by the cam 46 (Figs. 4 to 6). Either thepart 100 or the part 102 can be inoperative independently of the otherpart, leaving only one part in operation. The adherence of one of theprojections 97" and 97" against the part 100 or 102, respectively, ismaintained by a spring 103, one end 103 of which is fixed to the support104, while the other end 103 is connected to the lever 97, said end 103"of said spring keeping said lever pushed against either the pin 100 orthe pin 102 of the driving lever.

Assuming that the part 102 may be inoperative, the spring 103 will holdthe projection 97" against the part 100. When this part has beendisplaced, the projection 97" will follow it and consequently theslipper 98 will be displaced, said slipper constraining the fork 99 tomove and the runner 88 to slide upon the guiding pin 85 within thelimits 89-90. According to the position of the part 100, the runner orslider 88 will accomplish one determined stroke, said stroke beingrepeated by the fabric feeder.

If, on the contrary, the part 100 is inoperative and the part 102 is putin operation, this part 102 accomplishing automatic cyclicdisplacements, will compel the projection 97" to make correspondingdisplacements and similarly the fork 99, the link 91 and, consequently,the fabric feeder, the stroke amplitude and direction of Which willcontinuously vary for each stitch according to the shape of the camdriving the part 102.

The device will also work if both parts 100 and 102 are made operative,without any inconvenience being caused in the working, the one or theother of the parts 100, 102 effecting then the task of stroke limiter ofthe lever 97 and consequently of length limiter of the stitch.

It is clear that the construction of the parts hereinbefore describedcan vary from that shown in the drawings, the mechanism resulting fromtheir combination still remaining withinthe scope of the invention.

What I claim is: I

1. In a zig-zag sewing machine having a frame with a needle mechanismand work feeder therein, with two replaceable cams for the execution ofpattern sewing, one of which cams is for driving the transversedisplacements of the needle and the other of which cams is for drivingthe displacements of the work feeder, means for operatively connectingsaid second cam to the feeder comprising a two-armed lever, one arm ofsaid lever carrying a cam follower for receiving movement from saidsecond cam, means operatively connected with the other arm of said leverand to said feeder for controlling the movement of the feeder, a secondtwo-armed lever, means swingably mounting said second lever on themachine frame, means pivotally mounting the first lever on an arm of thesecond two-armed lever, and a manually operated eccentric cam engagingthe other arm of said second lever whereby operation of the eccentriccam results in a movement of the last-mentioned means of the firsttwo-armed lever along a circular line and in a corresponding variationof the movements of the feeder.

2. A zig-zag sewing machine according to claim 1 wherein the meansconnecting the first lever to the work feeder comprises a cross leverhaving three arms, a hand-operated pin mounted on said frame and beingin engagement with a first arm of said cross lever, said second arm ofthe first two-armed lever having a pin, the second arm of said crosslever being in engagement with said pin, an oscillating link operativelyconnected to the second arm of said first lever, said link having a forkengaging the third arm of said cross lever, to thereby transmit to theoscillating center of said link the displacements imparted in turn bythe other two arms of said cross lever.

3. A zig-zag sewing machine according to claim 2, wherein a light springkeeps the cross lever adherent to either the hand-operated pin or theeccentric cam.

4. A zig-zag sewing machine according to claim 2, wherein saidhand-operated pin operates said cross lever to impart simultaneously orseparately to said work feeder controlling and adjusting drives fromsaid eccentric cam and said hand-operated pin.

5. A zig-zag sewing machine according to claim 2, further comprising anoscillating guiding pin having a small angle of oscillation, a sliderslidably mounted on said guiding pin, said oscillating link connected tosaid slider whereby the oscillation produced by the guiding pin on saidwork feeder is small to prevent autonomous displacements of the slideron the guiding pin.

6. A zig-zag sewing machine according to claim 2, wherein a slipper ismounted at the end of the third arm of said cross lever and arranged toslide in said fork.

References Cited in the file of this patent UNITED STATES PATENTS696,039 Grothe Mar. 2, 1902 1,611,372 Rader Dec. 21, 1926 2,114,075Gellman Apr. 12, 1938 2,305,556 Pinkvoss Dec. 15, 1942 2,653,557Casas-Robert et al. Sept. 29, 1953 2,755,754 Urscheler July 24, 1956UNITED STATES PATENT. OFFICE CERTIFICATE OF CORRECTION Patent No.2,972,319 February 21 1961 Antonio Moro It is hereby certified thaterror appears in the above numbered patent requiring correction and thatthe said Letters Patent shouldread as corrected below.

d Column 2 line 6 for "positions Said" read position sal Signed andsealed this 151; day of May 1962.

(SEAL) Attest:

DAVID L. LADD ERNEST W, SWIDER Commissioner of Patents Attesting Officer

